Problem: $ { \left[\begin{array}{rrr}{1} & {2} & {1} \\ {0} & {4} & {-2}\end{array}\right]+\left[\begin{array}{rrr}{2} & {4} & {2} \\ {1} & {1} & {4}\end{array}\right] = {?} } $
Answer: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rrr}{1}+{2} & {2}+{4} & {1}+{2} \\ {0}+{1} & {4}+{1} & {-2}+{4}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{3} & {6} & {3} \\ {1} & {5} & {2}\end{array}\right]}$